Range Report smk's 175g. or 180g.- am I missing something?

[jjseman]

I'm having a really hard time finding .308 175g. SMK's locally, and every place I look on the web is on backorder. I was looking at the 180 grain SMK. From what I can tell, the b.c.'s are the same, if not, very close.
Why are 175 grain SMK's so much more popular than the 180 grain pills? I heard somebody suggesting the boat tail design is different. Then somewhere else I read that was a design of the past and it is not an issue currently. Aside from that, I don't know why you would decide on one over the other. Can you please clear things up for me.

 

[turbo54]

Re: smk's 175g. or 180g.- am I missing something?

I used to run the 180s. They shot well. Very well.

Here's the skinny:

High velocity BC is same as 175, but medium and low velocity BC is a bit higher with the 180, BUT, the 180 has the same boat tail the 168 has, which is what most folks believe is what causes the huge inconsistencies past ~750 with the 168s.

My personal experience with 180s was I could get them to ~2550-2600 from a 24" Savage that could run the 175s at ~2675.

The 175s were flatter to all practical ranges, and wind was a wash.

I did notice (unscientifically) that 180s were LESS consistent at 1000 yards than 175s.

I believe the boat tail design becomes an issue at lower velocities, making the slightly better BC (at lower speed) unusable.

That said, I'd not hesitate to run them again if 175s weren't available AND I had a max shooting range of ~800 yards or so.

43gr Varget was stiff, and yielded ~2575 from my 24" 10FP. I generally ran 42.5gr Varget for ~2550.

 

[jjseman]

Re: smk's 175g. or 180g.- am I missing something?

Thanks for the info. I found similar velocities and Max load pressures out of my Rra lar 8.

 

[agbm]

Brownells has them, in bulk pack 500 per case each.

 

[sinister]

Once upon a time (back before 175s) the military long range service rifle teams needed a 1,000 yard bullet for 22-inch barrel M14s shooting at Camp Perry. 173s were the issue bullet but quality was going into the toilet.

The Sierra 180 was an excellent bullet you could push to remain supersonic at 1,000 and it was very popular. For some reason Sierra changed the boat-tail to a shallower angle like the 168s. The bullet then began falling from favor.

The 180 Game King maintains the boat-tail angle of the original 180 Match King and has indeed won at Camp Perry despite being a soft point.

 

[mlw332]

brownells shipment of 500 i ordered last week came in today i would check them out

 

[CEL317]

brownells shipment of 500 i ordered last week came in today i would check them out

I have been checking there (and everywhere it seems like) and every time I do they are out of stock. Were they in stock or did you backorder them last week and get them this week?

 

[mlw332]

they were listed in stock when i purchased... i kept waiting for the were sorry email and finally the your shipment email came

 

[mlw332]

all i see they have in stock is 168 and 190 smk in bulk of 500

 

[CEL317]

I may have to go ahead and get 168's, but I keep hoping I'll find 175's somewhere.

 

[Trigger Time 23]

Powder Valley had some 175's a few days ago. Not sure if they still do, or not. Good luck.

 

[George63]

In other times, the 175's also shine for price - only 3 $ more per 500 than 168's

the 180's are usually a bigger jump in price

of course now you take what you can get

 

[ksthomas]

Sinister nailed this one precisely. The current 180 SMK is the result of management wanting to simplify tooling by using the same boat tail punches as those of the 168. The olde style 180 had the same BT angle as the 190s; considerably longer than the 168s. I argued (loudly) against this change, but was outvoted. The old style 180s worked beautifully, and were able to stay supersonic out of Service Rifles at 1,000, no problem. When they changed the BT, the new bullet became a real dog. It's pretty useless now, unless you're looking for a slightly heavier bullet to use at shorter ranges. It won't significantly improve over the range performance of the 168s, which is to say, it won't stay supersonic out of Service Rifle. The USAMU was still shooting M14s as their 1,000 yard guns at that point, and we continued to make the 180s for them on special contract runs; with the old design, and the old style BT.

The 175 came about as the result of a request from Lake City for a bullet that would stay supersonic at to 1,000 in 7.62x51 from service guns. After a BT change and some other tweeks, the current 175 gr. M118LR bullet is what resulted.

 

[Heman]

Kevin, maybe you can answer this question but why does Sierra refuse to update or improve their .30cal bullet lines? I have been emailing one of their ballisticians about taking the 142gr design or the 7mm 175gr design and making it into a 185gr .30cal which would be comparable to the 185gr Juggernaught. There bullets shoot but with Berger coming out with newer designs that are ballistically superior I don't understand why they wouldn't want to change. Obviously they have in the past with the 180gr and this was not for the better. Any light you could shed would be appreciated.

 

[dmike]

I used to run the 180s. They shot well. Very well.

Here's the skinny:

High velocity BC is same as 175, but medium and low velocity BC is a bit higher with the 180, BUT, the 180 has the same boat tail the 168 has, which is what most folks believe is what causes the huge inconsistencies past ~750 with the 168s.

My personal experience with 180s was I could get them to ~2550-2600 from a 24" Savage that could run the 175s at ~2675.

The 175s were flatter to all practical ranges, and wind was a wash.

I did notice (unscientifically) that 180s were LESS consistent at 1000 yards than 175s.

I believe the boat tail design becomes an issue at lower velocities, making the slightly better BC (at lower speed) unusable.

That said, I'd not hesitate to run them again if 175s weren't available AND I had a max shooting range of ~800 yards or so.

43gr Varget was stiff, and yielded ~2575 from my 24" 10FP. I generally ran 42.5gr Varget for ~2550.

Thanks for the great info, very helpful.

 

[Joea132]

Natchez has had 500 boxes of 175gr SMKs in stock for weeks, if not months. They're available, you just have to poke around

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